Holdover cold plate cooling unit

ABSTRACT

A cooling unit for and to be mounted within a container to be maintained refrigerated. The unit includes an open top tank having a closed hollow body removably positioned within the tank with general equal spacing between the inner surfaces of the tank walls and the opposing outer surfaces of the hollow body, the latter being somewhat less than completely filled with eutectic solution. The tank includes structure for mounting within the container to be refrigerated and is adapted to have liquid nitrogen discharged thereinto in sufficient quantity to lower the temperature of the hollow body and the eutectic solution disposed therein to the freezing point of the eutectic solution before all of the liquid nitrogen placed within the tank vaporizes.

Unite States Patet 1191 [111 3,744,271 1451 July 10; 1973 HOLDOVER COLD PLATE COOLING UNIT FOREIGN PATENTS 0R APPLICATIONS 1 lnvemofl Paul Franklin 5211 469,753 9/1937 Great Britain 62/7 Beaver St., Jacksonville, Fla. 32205 22 Filed: Mar. 31, 1972 Primary Examiner william J. Wye 1 pp NO I 240 047 Attorneyl-larvey B. Jacobson 57 ABSTRACT [52] U.S. Cl 62/430, 62/59, 62/514, I

2 57 2 43 A coollng unit for and to be mounted within a con- [51] llnt. Cl F25d 11/00 miner to b maintained refrigerated- The unit includes [58] Field of Search 62/59, 430, 64, 514, an p p tank having a closed hollow body remov- 2 57 20 4 5 ably positioned within the tank with general equal spacing between the inner surfaces of the tank walls and the 5 References Cited opposing outer surfaces of the hollow body, the latter UNITED STATES PATENTS being somewhat less than completely filled with eutectic solution. The tank includes structure for mounting l r P i' within the container to be refrigerated and is adapted 9/1941 'igf 62/457 to have liquid nitrogen discharged thereinto in suff1- 1982789 12/1934 Clark 62/59 cient quantity to lower the temperature of the hollow 3257820 6H9 Case body and the eutectic solution disposed therein to the 10/1971 a," 62/64 freezing point of the eutectic solution before all of 3:4l0:l09 H1968 'a'x I the liquid nitrogen placed within the tank vaporizes. 3,633,381 1/1972 Haaf 62/457 3,665,728 5 1972 Stoller 62/514 1 Chum, 3 Drawlng Figures.

t i i k z k t 74 50 50 56 I 5 i a---24 s 5* f l6 I-IOLDOVER COLD PLATE COOLING UNIT The main object of this invention is to provide a quick and inexpensive means for regrigerating the interior of an insulated container to maintain chilled foodstuffs and/or other materials disposed therein below a predetermined temperature in turn below the ambient temperature.

Another object of this invention is to provide a cooling unit in accordance with the preceding object and which may be mounted within a selected container to be repeatedly refrigerated with the container provided with liquid nitrogen ducting structure to be utilized in charging the tank of the cooling unit with the desired amount of liquid nitrogen in a safe manner from the exterior of the container.

A still further object of this invention is to provide a cooling unit in accordance with the preceding objects with the container including a low pressure differential actuated vent door whereby excess vaporized nitrogen discharged from the tank into the interior of the container may be vented from the latter.

A final object of this invention to be specifically enumerated herein is to provide a cooling unit for a container to be maintained refrigerated with the cooling unit being such as to conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part thereof, wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is a perspective view of the rear end of a truck having a refrigerated container to be maintained refrigerated by the cooling unit of the instant invention positioned therein;

FIG. 2 is an enlarged horizontal sectional view taken substantially upon the plane indicated by the section line 22 of FIG. 1; and

FIG. 3 is a vertical sectional view taken substantially upon the plane indicated by the section line 33 of FIG. 1.

Referring now more specifically to the drawings the numeral generally designates an enclosed body of a motor vehicle referred to in general by the reference numeral 12. An upright container 14 is illustrated positioned within the body 10 and it is to be understood that a plurality of the containers 14 may be positioned within the body 10 for transporting the containers 14 from a point of origin to various points of destination.

Although the containers 14 may be utilized to receive therein various types of commodities to be maintained refrigerated, one use of such containers resides in the placement of daily orders of foodstuffs within the containers for several distant restaurants, primarily of the drive-in type. After each container has been filled with the desired order it is placed upon the vehicle 12 and the latter is then utilized to transport the various con tainerized orders to several distant restaurants from a main supply point.

Each of the containers 14 includes insulated top and bottom walls 16 interconnected by means of front and rear walls 18 and 20 as well as opposite side walls 22 and 24. The front wall 18 of each container 14 has a large access opening 26 formed therein removably closable by means of a hinged front door 28. The side wall 24 has a large cross-sectional area vent opening 30 formed therein closed by means of a spring-urged and hinged closure door 32. Further, the side wall 24 includes an inwardly recessed portion 34 having a horizontal opening 36 formed therein and the inwardly recessed portion 34 defines an outwardly opening recess 38 for purpose to be hereinafter more fully set forth.

The cooling unit of the instant invention comprises an open top tank referred to in general by the reference numeral 40 and including front and rear walls 42 and 44 interconnected by means of opposite side walls 46 and 48. Also, the tank 40 includes a bottom wall 50 connecting the lower marginal portions of the walls 42, 44, 46 and 48.

A closed hollow body referred to in general by the reference numeral 52 is removably receivable within the tank 40. The body 52 includes top and bottom walls 54 and 56, opposite side walls 58 and 60, and front and rear walls 62 and 64;

The walls 42, 44, 46 and 48 as well as the bottom wall 50 having spacing angle members 42', 44', 46' and 48' as well as an angle member 50 supported therefrom and the angle members are utilized to support the hollow body 52 with the tank 40 with the inner surfaces of the various walls of the tank substantially equally spaced from the opposing outer surface portions of the hollow body 50.

The body 52 is substantially, but not completely, filled with a eutectic solution 66 and a body 68 of somewhat compressible material is disposed within the tank 40 and floats in the solution 66 when it is in a liquid state.

A delivery line 70 includes a fitting 72 on its inlet end and an outlet end 74 opening outwardly in the lower portion of the tank 40. The inlet end of the line 70 extends through the bore 36 and the fitting 72 is disposed in the recess 38.

In operation, a plurality of the containers 14 have predetermined orders of refrigerated foodstuffs placed therein and the doors 28 are then closed. Thereafter, liquid nitrogen of sufficient volume to freeze the eutectic solution 66 within the body 52 is piped into the tank 40 through the line 70. As the liquid nitrogen vaporizes the excess vapors within the container 14 are vented therefrom through the vent opening30 and any expansion of the eutectic solution 66 realized as the solution 66 is frozen by the liquid nitrogen within the tank 40 is compensated for by the compressible body 68.

Of course, the interior of the container 14 is immediately refrigerated by the quantity of the finally vaporized liquid nitrogen remaining in the container 14. Thereafter, refrigeration of the interior of the container 14 is maintained by the hollow body (or cold plate) 52 disposed within the tank 40. Of course, the amount of liquid nitrogen discharged into the tank 40 through the line 70 is in part determined by the freezing point of the eutectic solution 66.

After a plurality of the containers have been thus refrigerated, they may be lifted onto the vehicle 12 in any conventional manner and other foodstuffs and/or supplies may be disposed within the vehicle 12 exteriorly of the containers 14 before the vehicle 12 proceeds on its delivery route.

By utilizing the cooling unit of the instant invention containers such as the containers 14 may be rapidly refrigerated in a matter of five minutes or less without fear of mechanical breakdown and at a low cost.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired-to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1.,A cooling unit for and to be mounted within a container to be maintained refrigerated, said unit comprising an open top tank including upstanding peripheral wall portions interconnected at their lower ends by means of a bottom wall extending therebetween, a closed hollow body somewhat less than completely filled with eutectic solution and of a size and shape to be removably received within said tank with generally equal spacing between the inner surfaces of the bottom and peripheral walls of said tank and the opposing outer surfaces of said body and abutment means disposed between said opposing inner and outer surfaces for maintaining said generally equal spacing, said tank being adapted to have a liquid with a low boiling point discharged thereinto, an insulated container, said tank being mounted within said container, a liquid gas delivery line having an outlet end opening into said tank and an inlet end opening outwardly through one wall portion of said container, said one wall portion of said container comprising a portion of one upstanding wall of said container, said one wall portion being inwardly recessed relative to the adjacent portions of said one wall, said inlet end including means adapted for sealed communication with a source of liquid gas under pressure. 

1. A cooling unit for and to be mounted within a container to be maintained refrigerated, said unit comprising an open top tank including upstanding peripheral wall portions interconnected at their lower ends by means of a bottom wall extending therebetween, a closed hollow body somewhat less than completely filled with eutectic solution and of a size and shape to be removably received within said tank with generally equal spacing between the inner surfaces of the bottom and peripheral walls of said tank and the opposing outer surfaces of said body and abutment means disposed between said opposing inner and outer surfaces for maintaining said generally equal spacing, said tank being adapted to have a liquid with a low boiling point discharged thereinto, an insulated container, said tank being mounted within said container, a liquid gas delivery line having an outlet end opening into said tank and an inlet end opening outwardly through one wall portion of said container, said one wall portion of said container comprising a portion of one upstanding wall of said container, said one wall portion being inwardly recessed relative to the adjacent portions of said one wall, said inlet end including means adapted for sealed communication with a source of liquid gas under pressure. 